# UnitsConv vs smartHMI

The clearest difference is update cadence: UnitsConv at every 4 months against smartHMI's every 7 months. On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

UnitsConv ships an update every 4 months, smartHMI every 7 months. The most recent releases landed on September 10, 2026 and September 16, 2026 respectively.

## The numbers

| Metric | UnitsConv | smartHMI |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.3 (3 ratings)](https://appshunter.io/ios/app/unitsconv/id1291109803/reviews)** | — |
| Number of ratings | **3** | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 4 months** | Every 7 months |
| Monetization | Free | — |
| Size | 8 MB | 115 MB |
| Requires iOS | 12.0 | 12.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 17+ |
| Developer | [john selverian](https://appshunter.io/developer/1291109802) | [Siemens AG](https://appshunter.io/developer/394503271) |

## What reviewers say

### UnitsConv

[App page](https://appshunter.io/ios/app/unitsconv/id1291109803)

This app provides conversion factors for 28 common properties used in multiphysics simulations and finite element analysis. It's a free tool designed for engineers and researchers working with complex physical models.

**Highlights:** 28 conversion properties, Multiphysics simulation support, Finite element analysis (FEA) focus, Free to use, Supports iPhone, iPad, and iPod

**Features:** macOS Compatibility

**In-app purchases:** none


### smartHMI

[App page](https://appshunter.io/ios/app/smarthmi/id6448357450)

**In-app purchases:** none


## Frequently asked questions

### Is UnitsConv free?

UnitsConv is free to download, with no in-app purchases.

### Is smartHMI free?

smartHMI is free to download, with no in-app purchases.

### Do UnitsConv or smartHMI have ads?

Neither UnitsConv nor smartHMI shows ads.

### Which is updated more often, UnitsConv or smartHMI?

UnitsConv ships an update every 4 months, and smartHMI every 7 months. Most recently, UnitsConv was updated on September 10, 2026 and smartHMI on September 16, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*